Teruo Yamamori

Reactions of nitrile oxides with 2-lithio-1,3-dithianes synthesis of α-diketones

Abstract Nitrile oxides (2) were treated with 2-lithio-1,3-dithianes (4) to give in good yields masked ketoximes (5), new synthetic tools for a α-diketones.

Studies on dihydropyridine derivatives-I: 4,7-dihydroisoxazolo[5,4-b]pyridines

Abstract Reactions of 5-aminoisoxazoles with α,β-unsaturated ketones in t-butanol on heating afforded 4,7-dihydroisoxazolo [5,4-b]pyridines. However, when the reactions were carried out at 20° using ethylene glycol as the solvent, the kinetically controlled amino adducts were obtained in excellent yields. The amino adducts were converted into the thermodynamically controlled 4,7-dihydroisoxazolo[5,4-b]pyridines by heating. Tentative mechanisms for the reactions are also presented.

Studies on tertiary amine oxides—LII: Reaction of 4-nitroquinoline 1-oxide with enamines of isobutyraldehyde. A novel cyclization reaction involving participation of the nitro group☆

Abstract When a chloroform solution of 4-nitroquinoline 1-oxide ( 1 ) and 2 equivalents of an enamine of isobutyraldehyde ( 4 ) is kept at room temp for a prolonged time, a novel cyclization reaction occurs to produce 1-hydroxy-2-oxo-3,3-dimethylpyrrolido[4,5-c]quinoline 5-oxide ( 5 ) or/and the corresponding 1-deoxy compound ( 6 ). Their structures were established by spectral and chemical examinations. The reaction mechanisms are also discussed.